Write-based data management using endurance tiers in a storage system

ABSTRACT

A method, system, and computer program product manages a storage system. Writes to sections in solid state storage devices in endurance tiers in the storage system are monitored by a computer system over a period of time. Responsive to a write rate for the writes to a section in the sections in an current endurance tier in the endurance tiers exceeding a maximum recommended write rate for the current endurance tier during the period of time, data is moved from the section in the current endurance tier to a higher endurance tier in the endurance tiers having a higher maximum recommended write rate than the maximum recommended write rate for the current endurance tier.

BACKGROUND 1. Field

The disclosure relates generally to an improved computer system and,more specifically, to a method, apparatus, computer system, and computerprogram product to manage data written to a storage system.

2. Description of the Related Art

Solid state storage devices are commonly used for data operationsinvolving storage devices that require high input and outputperformance. Solid state storage devices can have high performanceadvantages over drives using spinning discs when workloads includerandom read and write patterns.

Solid state storage devices can include, for example, solid statedrives, flash drives, and other similar devices. Many of these devicesinclude memory comprised of NAND gates. With this technology, solidstate storage devices will last for a period of time specified by themanufacturer when the solid state storage devices are written to a ratethat is not greater than a manufacturer's specification.

SUMMARY

According to one embodiment of the present invention, a method manages astorage system. Writes to sections in solid state storage devices inendurance tiers in the storage system are monitored by a computer systemover a period of time. Responsive to a write rate for the writes to asection in the sections in an current endurance tier in the endurancetiers exceeding a maximum recommended write rate for the currentendurance tier during the period of time, data is moved by the computersystem from the section in the current endurance tier to a higherendurance tier in the endurance tiers having a higher maximumrecommended write rate than the maximum recommended write rate for thecurrent endurance tier.

According to another embodiment of the present invention, a storagemanagement system comprises a computer system that monitors writes tosections in solid state storage devices in endurance tiers of in astorage system over a period of time. Responsive to a write rate for thewrites to a section in the sections in an current endurance tier in theendurance tiers exceeding a maximum recommended write rate for thecurrent endurance tier during the period of time, the computer systemmoves data from the section in the current endurance tier to a higherendurance tier in the endurance tiers having a higher maximumrecommended write rate than the maximum recommended write rate for thecurrent endurance tier.

According to yet another embodiment of the present invention, a computerprogram product for managing a storage system comprises acomputer-readable-storage media with first program code and secondprogram code stored on the computer-readable storage media. The firstprogram code is executable by a computer system to cause the computersystem to monitor writes to sections in solid state storage devices inendurance tiers of in the storage system over a period of time. Thesecond program code is executable by a computer system to cause thecomputer system to move data from a section in the sections in a currentendurance tier to a higher endurance tier in the endurance tiers havinga higher maximum recommended write rate than a maximum recommended writerate for the current endurance tier in response to the write rate forthe writes to the section exceeding the maximum recommended write ratefor the current endurance tier during the period of time.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a pictorial representation of a network of data processingsystems in which illustrative embodiments may be implemented;

FIG. 2 is a block diagram of a storage environment in accordance with anillustrative embodiment;

FIG. 3 is a flowchart of a process for managing a storage system inaccordance with an illustrative embodiment;

FIG. 4 is a flowchart of a process for moving data to another endurancetier in accordance with an illustrative embodiment;

FIG. 5 is a flowchart of a process for configuring a storage system inaccordance with an illustrative embodiment;

FIG. 6 is a flowchart of a process for provisioning a storage system inaccordance with an illustrative embodiment; and

FIG. 7 is a block diagram of a data processing system in accordance withan illustrative embodiment.

DETAILED DESCRIPTION

The present invention may be a system, a method, and/or a computerprogram product at any possible technical detail level of integration.The computer program product may include a computer-readable storagemedium (or media) having computer-readable program instructions thereonfor causing a processor to carry out aspects of the present invention.

The computer-readable storage medium can be a tangible device that canretain and store instructions for use by an instruction executiondevice. The computer-readable storage medium may be, for example, but isnot limited to, an electronic storage device, a magnetic storage device,an optical storage device, an electromagnetic storage device, asemiconductor storage device, or any suitable combination of theforegoing. A non-exhaustive list of more specific examples of thecomputer-readable storage medium includes the following: a portablecomputer diskette, a hard disk, a random access memory (RAM), aread-only memory (ROM), an erasable programmable read-only memory (EPROMor Flash memory), a static random access memory (SRAM), a portablecompact disc read-only memory (CD-ROM), a digital versatile disk (DVD),a memory stick, a floppy disk, a mechanically encoded device such aspunch-cards or raised structures in a groove having instructionsrecorded thereon, and any suitable combination of the foregoing. Acomputer-readable storage medium, as used herein, is not to be construedas being transitory signals per se, such as radio waves or other freelypropagating electromagnetic waves, electromagnetic waves propagatingthrough a waveguide or other transmission media (e.g., light pulsespassing through a fiber-optic cable), or electrical signals transmittedthrough a wire.

Computer-readable program instructions described herein can bedownloaded to respective computing/processing devices from acomputer-readable storage medium or to an external computer or externalstorage device via a network, for example, the Internet, a local areanetwork, a wide area network and/or a wireless network. The network maycomprise copper transmission cables, optical transmission fibers,wireless transmission, routers, firewalls, switches, gateway computersand/or edge servers. A network adapter card or network interface in eachcomputing/processing device receives computer-readable programinstructions from the network and forwards the computer-readable programinstructions for storage in a computer-readable storage medium withinthe respective computing/processing device.

Computer-readable program instructions for carrying out operations ofthe present invention may be assembler instructions,instruction-set-architecture (ISA) instructions, machine instructions,machine dependent instructions, microcode, firmware instructions,state-setting data, configuration data for integrated circuitry, oreither source code or object code written in any combination of one ormore programming languages, including an object oriented programminglanguage such as Smalltalk, C++, or the like, and procedural programminglanguages, such as the “C” programming language or similar programminglanguages. The computer-readable program instructions may executeentirely on the user's computer, partly on the user's computer, as astand-alone software package, partly on the user's computer and partlyon a remote computer or entirely on the remote computer or server. Inthe latter scenario, the remote computer may be connected to the user'scomputer through any type of network, including a local area network(LAN) or a wide area network (WAN), or the connection may be made to anexternal computer (for example, through the Internet using an InternetService Provider). In some embodiments, electronic circuitry including,for example, programmable logic circuitry, field-programmable gatearrays (FPGA), or programmable logic arrays (PLA) may execute thecomputer-readable program instructions by utilizing state information ofthe computer-readable program instructions to personalize the electroniccircuitry, in order to perform aspects of the present invention.

Aspects of the present invention are described herein with reference toflowchart illustrations and/or block diagrams of methods, apparatus(systems), and computer program products according to embodiments of theinvention. It will be understood that each block of the flowchartillustrations and/or block diagrams, and combinations of blocks in theflowchart illustrations and/or block diagrams, can be implemented bycomputer-readable program instructions.

These computer-readable program instructions may be provided to aprocessor of a computer, or other programmable data processing apparatusto produce a machine, such that the instructions, which execute via theprocessor of the computer or other programmable data processingapparatus, create means for implementing the functions/acts specified inthe flowchart and/or block diagram block or blocks. Thesecomputer-readable program instructions may also be stored in acomputer-readable storage medium that can direct a computer, aprogrammable data processing apparatus, and/or other devices to functionin a particular manner, such that the computer-readable storage mediumhaving instructions stored therein comprises an article of manufactureincluding instructions which implement aspects of the function/actspecified in the flowchart and/or block diagram block or blocks.

The computer-readable program instructions may also be loaded onto acomputer, other programmable data processing apparatus, or other deviceto cause a series of operational steps to be performed on the computer,other programmable apparatus or other device to produce a computerimplemented process, such that the instructions which execute on thecomputer, other programmable apparatus, or other device implement thefunctions/acts specified in the flowchart and/or block diagram block orblocks.

The flowchart and block diagrams in the figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer program products according to variousembodiments of the present invention. In this regard, each block in theflowchart or block diagrams may represent a module, segment, or portionof instructions, which comprises one or more executable instructions forimplementing the specified logical function(s). In some alternativeimplementations, the functions noted in the blocks may occur out of theorder noted in the figures. For example, two blocks shown in successionmay, in fact, be accomplished as one step, executed concurrently,substantially concurrently, in a partially or wholly temporallyoverlapping manner, or the blocks may sometimes be executed in thereverse order, depending upon the functionality involved. It will alsobe noted that each block of the block diagrams and/or flowchartillustration, and combinations of blocks in the block diagrams and/orflowchart illustration, can be implemented by special purposehardware-based systems that perform the specified functions or acts orcarry out combinations of special purpose hardware and computerinstructions.

Illustrative embodiments recognize and take into account a number ofdifferent considerations. For example, the illustrative embodimentsrecognize and take into account that an endurance of a solid statestorage device can be described in terms of drive writes per day (DWPD).The illustrative embodiments recognize and take into account that themanufacturer specifies the number of drive writes per day that can beperformed and maintain the warranty. The illustrative embodimentsrecognize and take into account that manufacturers have offered lowerendurance options for solid state storage devices in an effort to reducethe cost of these devices. For example, a more economical solid statestorage device can have one drive write per day and higher-quality, moreexpensive solid state storage devices can have five drive writes perday.

The illustrative embodiments recognize and take into account that toavoid having customers take advantage of warranty services, hardwaremanufacturers will often have the drives fail with a specific error codewhen the drives have exceeded their write rating. When the drive failswith the error code, the customer is required to pay for the replacementbecause the drive has been overused. The illustrative embodimentsrecognize and take into account that this situation causes customers tomake decisions at a time of purchase on which type or types of storageto use and which workload to place on them. The decisions on use andworkload can be inexact resulting in unnecessary costs or poor usage ofthe solid state storage devices. The illustrative embodiments recognizeand take into account that even if the design is perfectly aligned withactual consumption, placement decisions are still needed at the logicalunit number (LUN) and volume level. Those embodiments recognize and takeinto account that within many workloads, such as relational databases,some portions of the database are much more dynamic than others andtherefore generate higher write levels. The illustrative embodimentsrecognize and take into account that allocating drive space based onvolume is too coarse of a selection to avoid placing the less activeportions of the volume on a high endurance disk.

The illustrative embodiments recognize and take into account that itwould be desirable to have a method and apparatus that take into accountat least some of the issues discussed above, as well as other possibleissues. For example, it would be desirable to have a method andapparatus that overcome a problem with managing a storage system usingsolid state storage devices in a manner that reduces situations inwrites to solid state storage devices exceeding a manufacturer specifiedrate for warranty purposes.

Thus, the illustrative embodiments provide a method, apparatus, computersystem, and computer program product for managing a storage system.Writes to sections in solid state storage devices in endurance tiers inthe storage system are monitored by a computer system over a period oftime. Responsive to a write rate for the writes to a section in thesections in an current endurance tier in the endurance tiers exceeding amaximum recommended write rate for the current endurance tier during theperiod of time, data is moved from the section in the current endurancetier to a higher endurance tier in the endurance tiers having a highermaximum recommended write rate than the maximum recommended write ratefor the current endurance tier.

With reference now to the figures and, in particular, with reference toFIG. 1, a pictorial representation of a network of data processingsystems is depicted in which illustrative embodiments may beimplemented. Network data processing system 100 is a network ofcomputers in which the illustrative embodiments may be implemented.Network data processing system 100 contains network 102, which is themedium used to provide communications links between various devices andcomputers connected together within network data processing system 100.Network 102 may include connections, such as wire, wirelesscommunication links, or fiber optic cables.

In the depicted example, server computer 104 and server computer 106connect to network 102 along with storage system 108. In addition,client devices 110 connect to network 102. As depicted, client devices110 include client computer 112, client computer 114, and clientcomputer 116. Client devices 110 can be, for example, computers,workstations, or network computers. In the depicted example, servercomputer 104 provides information, such as boot files, operating systemimages, and applications to client devices 110. Further, client devices110 can also include other types of client devices such as mobile phone118, tablet computer 120, and smart glasses 122. In this illustrativeexample, server computer 104, server computer 106, storage system 108,and client devices 110 are network devices that connect to network 102in which network 102 is the communications media for these networkdevices. Some or all of client devices 110 may form anInternet-of-things (IoT) in which these physical devices can connect tonetwork 102 and exchange information with each other over network 102.

Client devices 110 are clients to server computer 104 in this example.Network data processing system 100 may include additional servercomputers, client computers, and other devices not shown. Client devices110 connect to network 102 utilizing at least one of wired, opticalfiber, or wireless connections.

Program code located in network data processing system 100 can be storedon a computer-recordable storage medium and downloaded to a dataprocessing system or other device for use. For example, program code canbe stored on a computer-recordable storage medium on server computer 104and downloaded to client devices 110 over network 102 for use on clientdevices 110.

In the depicted example, network data processing system 100 is theInternet with network 102 representing a worldwide collection ofnetworks and gateways that use the Transmission ControlProtocol/Internet Protocol (TCP/IP) suite of protocols to communicatewith one another. At the heart of the Internet is a backbone ofhigh-speed data communication lines between major nodes or hostcomputers consisting of thousands of commercial, governmental,educational, and other computer systems that route data and messages. Ofcourse, network data processing system 100 also may be implemented usinga number of different types of networks. For example, network 102 can becomprised of at least one of the Internet, an intranet, a local areanetwork (LAN), a metropolitan area network (MAN), or a wide area network(WAN). FIG. 1 is intended as an example, and not as an architecturallimitation for the different illustrative embodiments.

As used herein, “a number of,” when used with reference to items, meansone or more items. For example, “a number of different types ofnetworks” is one or more different types of networks.

Further, the phrase “at least one of,” when used with a list of items,means different combinations of one or more of the listed items can beused, and only one of each item in the list may be needed. In otherwords, “at least one of” means any combination of items and number ofitems may be used from the list, but not all of the items in the listare required. The item can be a particular object, a thing, or acategory.

For example, without limitation, “at least one of item A, item B, oritem C” may include item A, item A and item B, or item B. This examplealso may include item A, item B, and item C or item B and item C. Ofcourse, any combinations of these items can be present. In someillustrative examples, “at least one of” can be, for example, withoutlimitation, two of item A; one of item B; and ten of item C; four ofitem B and seven of item C; or other suitable combinations.

In the illustrative example, storage system 124 and storage system 126are also present in network data processing system 100 in addition tostorage system 108. As depicted, storage system 124 is connected toserver computer 104, and storage system 126 is connected to clientcomputer 112 instead of being connected to network 102.

These storage systems include solid state storage devices (SSSDs).Within a storage system, a solid state storage devices can be organizedinto hierarchies of endurance tiers in a storage system. Each endurancetier can include a class of storage having a particular maximum writerate specified by a manufacturer.

As depicted, storage manager 130 is located in server computer 104 andoperates to manage at least one of storage system 108, storage system124, and storage system 126. In the illustrative example, storagemanager 130 can manage where data is stored in different sections of thesolid state storage devices. This management can include moving datawritten to sections when the writes for that data are greater than somedesired threshold based on endurance of the solid state storage deviceson which the data is located.

For example, storage manager 130 can monitor writes to sections in solidstate storage devices (SSSDs) 132 in endurance tiers 134 in storagesystem 124 over a period of time. In this depicted example, the periodof time can be, for example, three days or four days. Other periods oftime can be selected depending on the particular implementation.

When the writes to a section in a solid state storage device in anendurance tier are greater than a recommended maximum write rate for theendurance tier, the data in the section can be moved to a section in ahigher endurance tier in endurance tiers 134 having a higher maximumrecommended write rate for data. A similar process can be performed tomove data to a lower endurance tier when the writes fall below a minimumrecommended write rate for a solid state storage device in an endurancetier in endurance tiers 134. Moving data to a lower endurance tier freesup space for data that have higher write rates such that the use ofstorage space in storage system 124 can be improved or optimized.

As a result, the writing of data to solid state storage devices in atleast one of storage system 124, storage system 126, or storage system108 can be managed in a manner that avoids write rates that exceed themaximum specified by manufacturers. With this type of management of datasolid state storage devices, the life of storage devices can beincreased and warranties for manufacturers can be maintained by notexceeding the maximum write rates specified for solid state storagedevices.

In other illustrative examples, in managing multiple storage systems,storage manager 130 can be in a single location such as server computer104 or can be distributed to at least one of client computer 112,storage system 108, or in some other computer or data processing systemin network data processing system 100. Storage manager 130 can bedistributed in which instances of storage manager 130 are located inserver computer 104, client computer 112, and storage system 108. Inother examples, storage manager 130 can be distributed using aserver-client software architecture.

With reference now to FIG. 2, a block diagram of a storage environmentis depicted in accordance with an illustrative embodiment. In thisillustrative example, storage environment 200 includes components thatcan be implemented in hardware such as the hardware shown in networkdata processing system 100 in FIG. 1.

In this illustrative example, storage management system 202 managesstorage system 204. The management of storage system 204 by storagemanagement system 202 includes at least one of writing, reading, orstoring data 206 in storage system 204.

As depicted, storage system 204 comprises solid state storage devices.The solid state storage devices can take a number of different forms.For example, the solid state storage devices can comprise at least oneof a solid state disk, a flash drive, or some other suitable type ofstorage device.

In this illustrative example, solid state storage devices 208 andstorage system 204 are in endurance tiers 210. Endurance tiers 210 areorganized in hierarchy 212. As depicted, hierarchy 212 of endurancetiers 210 is based on maximum recommended write rates 214 for endurancetiers 210 of solid state storage devices 208 in this example.

Storage management system 202 comprises storage manager 216 in computersystem 218. Storage manager 216 is located in computer system 218.Storage manager 216 can be implemented in software, hardware, firmware,or a combination thereof. When software is used, the operationsperformed by storage manager 216 can be implemented in program codeconfigured to run on hardware, such as a processor unit. When firmwareis used, the operations performed by storage manager 216 can beimplemented in program code and data and stored in persistent memory torun on a processor unit. When hardware is employed, the hardware mayinclude circuits that operate to perform the operations in storagemanager 216.

In the illustrative examples, the hardware may take a form selected fromat least one of a circuit system, an integrated circuit, an applicationspecific integrated circuit (ASIC), a programmable logic device, or someother suitable type of hardware configured to perform a number ofoperations. With a programmable logic device, the device can beconfigured to perform the number of operations. The device can bereconfigured at a later time or can be permanently configured to performthe number of operations. Programmable logic devices include, forexample, a programmable logic array, a programmable array logic, a fieldprogrammable logic array, a field programmable gate array, and othersuitable hardware devices. Additionally, the processes can beimplemented in organic components integrated with inorganic componentsand can be comprised entirely of organic components excluding a humanbeing. For example, the processes can be implemented as circuits inorganic semiconductors.

Computer system 218 is a physical hardware system and includes one ormore data processing systems. When more than one data processing systemis present in computer system 218, those data processing systems are incommunication with each other using a communications medium. Thecommunications medium can be a network. The data processing systems canbe selected from at least one of a computer, a server computer, a tabletcomputer, or some other suitable data processing system.

In managing data 206 for storage system 204, storage manager 216 incomputer system 218 can manage the storage of data 206 based on writes220 to solid state storage devices 208 in storage system 204. Forexample, storage manager 216 can monitor writes 220 to sections 222 insolid state storage devices 208 in endurance tiers 210 in storage system204 over a period of time.

Sections 222 can take a number of different forms. For example, sections222 can include at least one of a segment, an extent, a data block, orsome other suitable allocation or grouping of storage in a storagedevice. As depicted, a data block corresponds to a number of bytes ofphysical space on a disk. An extent is a number of continuous datablocks. A segment is a set of extents in this illustrative example.

Data 206 stored in sections 222 can take a number of different forms.For example, data 206 may be records for a database, an image, an audiofile, a spreadsheet, or some other type of data. Data 206 in aparticular section may be written to more often depending on the type ofdata or the use of the data in that particular section. For example,data 206 in the particular section may be for a database written toperform commercial transactions. That particular section may be writtento more often as compared to data in the form of an archived documentstored in another section in sections 222.

The period of time can take a number of different forms. For example,the period of time can be 10 hours, 33 hours, three days, six days, oneweek, or some other suitable period of time. Writes 220 can be measuredin a number of different ways. For example, writes 220 can be measuredas one of a running daily average, an average during the period of time,an aggregate total in the period of time, or some other suitable mannerin which writes 220 can be measured.

In monitoring writes 220 to sections 222 in solid state storage device208, writes 220 to each section in sections 222 are monitored in theillustrative example. These writes can also be referred to as writelevels. Responsive to write rate 230 for writes 220 to section 228 insections 222 in current endurance tier 232 in endurance tiers 210exceeding maximum recommended write rate 234 for current endurance tier232 during period of time 224, storage manager 216 moves data 226 fromsection 228 in current endurance tier 232 to higher endurance tier 236in endurance tiers 210 having higher maximum recommended write rate 238than maximum recommended write rate 234 for current endurance tier 232.In this example, data 226 is moved from section 228 to another sectionin higher endurance tier 236.

As depicted, maximum recommended write rate 234 is a threshold value.Maximum recommended write rates 214 for endurance tiers 210 for solidstate storage devices 208 are lower than the maximum write ratesspecified by a manufacturer of the solid state storage devices. Themaximum write rate specified by the manufacturer can be measured, forexample, as drive writes per day (DWPD), gigabyte (GB) writes per day,or some other metric. Exceeding this manufacturer specified the writelevel can void a warranty for the solid state drive.

In the illustrative example, maximum recommended write rates 214 areselected to be lower than the maximum write rates to help avoid warrantyissues. For example, a solid state drive can have gigabyte writes perday of 24.6 gigabytes. In other words, storage manager 216 can move data226 to different sections in sections 222 in a manner that reduces oravoids exceeding maximum write rates specified by a manufacturer inthese illustrative examples.

Further, responsive to write rate 230 for writes 220 to section 228 incurrent endurance tier 232 falling below minimum recommended write rate240 for current endurance tier 232 during period of time 224, storagemanager 216 moves data 226 from section 228 in current endurance tier232 to lower endurance tier 242 in endurance tiers 210 with lowerminimum recommended write rate 244 than minimum recommended write rate240 for current endurance tier 232. In other words, minimum recommendedwrite rate 244 for lower endurance tier 242 is lower than minimumrecommended write rate 240 for current endurance tier 232.

In the illustrative example, lower endurance tier 242 can include solidstate storage devices 208 that are more economical or less costly priceas compared to solid state storage devices 208 in higher endurance tier236. As a result, the higher recommended write rates in higher endurancetiers can be saved for data that takes advantage of needs for the higherwrite rates in the endurance tiers. This type of data managementoptimizes the use of storage space in storage system 204 in theillustrative example.

In the illustrative example, minimum recommended write rate 240 isselected to move data to a lower tier when the write rates in thecurrent tier are lower than some minimum. In this manner, space can befreed up in the current tier for writing data that have higher writerates than minimum recommended write rate 240. In the illustrativeexample, minimum recommended write rate 240 for current endurance tier232 is based on maximum recommended write rate 243 for lower endurancetier 242.

In this illustrative example, lower endurance tier 242 can be anentry-level tier within maximum write rate of 1.0 daily write per day(DWPD) specified by the manufacturer. Current endurance tier 232 can bea mid-level tier with a maximum write rate of 3.0 DWPD specified by themanufacturer. In selecting recommended write rates, it can be desirableto avoid situations where maximum recommended write rate 243 for lowerendurance tier 242 is at the cutoff of the maximum write rate specifiedby the manufacturer for lower endurance tier 242.

With this goal in mind, maximum recommended write rate 243 can be setwith a buffer fro r the maximum write rate specified by themanufacturer. For example, the buffer can be 0.15 DWPD, resulting in0.85 DWPD for maximum recommended write rate 243 for lower endurancetier 242.

In this illustrative example, minimum recommended write rate 240 can beselected to move data 206 from current endurance tier 242 to lowerendurance tier 242 in a manner that avoids data 206 being moved up anddown between current endurance tier 232 and lower endurance tier 242 atan undesired rate. For example, minimum recommended write rate 240 canbe selected as 0.80 DWPD.

When storage manager 216 decides to move data 226 from section 228 incurrent endurance tier 232 to another endurance tier 246 in endurancetiers 210, storage manager 216 determines whether another endurance tier226 has sufficient storage to store data 226 currently located insection 228 of current endurance tier 232 in response to anotherendurance tier 246 being selected to perform a movement of data 226.Storage manager 216 generates alert 248 indicating that insufficientstorage 250 is present for the movement of data 226 in response toanother endurance tier 246 having insufficient storage 250 for data 226in section 228 of current endurance tier 232.

In one illustrative example, one or more solutions are present thatovercome a problem with managing a storage system using solid statestorage devices in a manner that reduces situations in writes to solidstate storage devices exceeding a manufacturer specified rate forwarranty purposes. As a result, one or more solutions may provide aneffect of avoiding writes exceeding manufacturer write rates bymonitoring writes and relocating data within endurance tiers of solidstate devices having different maximum recommended write rates in amanner that optimizes the use of a storage system without exceedingmaximum recommended write rates assigned to different endurance tiers.

Computer system 218 can be configured to perform at least one of thesteps, operations, or actions described in the different illustrativeexamples using software, hardware, firmware, or a combination thereof.As a result, computer system 218 operates as a special purpose computersystem in which storage manager 216 in computer system 218 enablesmanaging the writing of data to different solid state storage devices instorage system 204. The grouping of solid state storage device 208 inendurance tiers 210 with hierarchy 212 based on maximum recommendedwrite rates 214 can be used to manage where data 206 is stored in writes220 to data 206 stored within endurance tiers 210. In particular,storage manager 216 transforms computer system 218 into a specialpurpose computer system as compared to currently available generalcomputer systems that do not have storage manager 216. As a result,storage manager 216 performs write-based data management using endurancetiers 210 in storage system 204.

In the illustrative example, the use of storage manager 216 in computersystem 218 integrates processes into a practical application for amethod of managing storage systems that increases the performance ofcomputer system 218. In other words, storage manager 216 in computersystem 218 is directed to a practical application of processesintegrated into storage manager 216 in computer system 218 that monitorswrites 220 to solid state storage devices 208 organized in endurancetiers 210 having hierarchy 212 in which hierarchy 212 is based onmaximum recommended write rates 214. Writes 220 to sections 222 inendurance tiers 210 are monitored in the illustrative example. Whenwrites for a section exceed maximum recommended write rates for aparticular endurance tier, the data in that section can be moved toanother endurance tier in the hierarchy having a higher maximumrecommended write rate that is sufficient for the rate detected.

As a result, exceeding manufacture write rates can be avoided. By notexceeding manufacturer write rates, the life of solid state storagedevices 208 in storage system 204 can be increased and the voiding ofwarranties for solid state storage devices 208 can be reduced oravoided. In this manner, storage manager 216 in computer system 218provides a practical application of managing writes to storage devicessuch that the functioning of computer system 218 is improved. As aresult, undesired and unexpected failures in storage solid state storagedevices 208 can be reduced using storage manager 216 to manage writes220 of data 206 to solid state storage devices 208. As a result, thereliability of computer system 218 with respect to storing data 206 canbe improved as compared to current computer systems that do not employstorage manager 216.

Additionally, a reduction in expense can be realized by users orcustomers employing storage manager 216 to manage storage system 204 incontrast to the current practice of users having to predict or guess ataverage write levels across a broad workload and using right levelingalgorithms within the solid state drives to manage usage of thosedrives. Current techniques for a large-scale redundant array ofinexpensive disks (RAID) sets using distributed RAID (DRAID) and othersimilar technologies rely on hotspots being spread across multipledrives as a side effect of RAID usage. Storage manager 216 can manageworkloads more efficiently and in a more cost-effective manner.

In one example, a backup application can utilize a relational databasemanagement system (RDMS) such as Db2 to store metadata. This type ofimplementation can require the use of performance of solid state storagedevices. The backup data can have a much lower write rate as compared tothe metadata. The primary writes for the backup data can be related tode-duplication metadata tracking. With current implementations, backupdata and metadata are placed on the same RAID array. The solid statedisks for the RAID array are selected to support the higher level ofwrites for the metadata.

Current storage systems do not consider using separate RAID arrays inthe same storage system for moving data. As a result, with the currenttechniques, higher performance storage arrays are used when only a smallportion of the data needs the higher write rates. The illustrativeexamples recognize and take into account that write wear overload can beavoided by placing data on a different RAID arrays in the same storagesystem in which the RAID arrays can be endurance tiers.

With storage manager 216, the writing of these different types of datacan be managed using solid state storage devices 208 organized inendurance tiers 210. As a result, metadata can be written in a higherendurance tier as compared to the backup data. In the illustrativeexample, the monitoring of writes by storage manager 216 are performedon a set volume level, such as sections in the form of extensorsegments.

In this example implementation, storage manager 216 can automaticallymove or migrate data, such as metadata or backup data, based on writerates without needing user input or specific provisioning of solid statedrives for particular types of data. With this type of implementation,each metadata and backup data can be placed in different endurancetiers. Storage manager 216 can be configured to track writes of datawithin a period of time that is selected to focus on longer-term writessuch as a week as compared to writes performed within a shorter periodof time such as the past day.

The illustration of storage environment 200 in FIG. 2 is not meant toimply physical or architectural limitations to the manner in which anillustrative embodiment can be implemented. Other components in additionto or in place of the ones illustrated may be used. Some components maybe unnecessary. Also, the blocks are presented to illustrate somefunctional components. One or more of these blocks may be combined,divided, or combined and divided into different blocks when implementedin an illustrative embodiment.

For example, storage manager 216 can be used to manage one or morestorage systems in addition to or in place of storage system 204.Further, storage system 204 is shown in a single block. Solid statestorage devices 208 can be located in the same physical location ordistributed in different locations depending on the particularimplementation. Further, the moving of data based on a minimumrecommended write rate is an optional feature and may not be implementedin storage manager 216 in some illustrative examples. Further, inmonitoring writes 220 to section 228, storage manager 216 may monitorwrites 220 in other sections in sections 222. These other sections maybe monitored in conjunction with section 228 such that data 226 in thesections can be moved to another endurance tier as a group when one ofthe sections exceeds a maximum recommended write rate even though othersections may not exceed the maximum recommended write rate. Further,storage manager 216 can operate to manage many different types ofstorage systems and applications for storage systems.

Turning next to FIG. 3, a flowchart of a process for managing a storagesystem is depicted in accordance with an illustrative embodiment. Theprocess in FIG. 3 can be implemented in hardware, software, or both.When implemented in software, the process can take the form of programcode that is run by one or more processor units located in one or morehardware devices in one or more computer systems. For example, theprocess can be implemented in storage manager 216 in computer system 218in FIG. 2.

The process begins by monitoring writes to sections in solid statestorage devices in endurance tiers in a storage system over a period oftime (operation 300). Responsive to a write rate for the writes to asection in the sections in a current endurance tier in the endurancetiers exceeding a maximum recommended write rate for the currentendurance tier during the period of time, the process moves data from asection in a current endurance tier to a higher endurance tier in theendurance tiers having a higher maximum recommended write rate than themaximum recommended write rate for the current endurance tier (operation302).

Responsive to the write rate for the writes to the section in thecurrent endurance tier falling below a minimum recommended write ratefor the current endurance tier during the period of time, the processmoves the data from the section in the current endurance tier to a lowerendurance tier in the endurance tiers with a lower minimum recommendedwrite rate than the minimum recommended write rate for the currentendurance tier (operation 304). The process terminates thereafter.

With reference next to FIG. 4, a flowchart of a process for moving datato another endurance tier is depicted in accordance with an illustrativeembodiment. The process in FIG. 4 can be implemented in hardware,software, or both. When implemented in software, the process can takethe form of program code that is run by one or more processor unitslocated in one or more hardware devices in one or more computer systems.For example, the process can be implemented in storage manager 216 incomputer system 218 in FIG. 2. The process in this flowchart can be usedto move data to a higher endurance tier such as in operation 302 or alower endurance tier such as in operation 304 in FIG. 3.

The process begins by identifying another endurance tier for moving datain a segment in a current endurance tier (operation 400). The endurancetier can be a higher endurance tier or a lower endurance tier.

The process determines whether another endurance tier has sufficientstorage for data in the section in the current endurance tier inresponse to another endurance tier being selected to perform a movementof the data (operation 402). If sufficient space is present, the processmoves the data to the another endurance tier (operation 404). Theprocess terminates thereafter.

Otherwise, the process generates an alert indicating that insufficientstorage is present for the movement of the data (operation 406) with theprocess terminating thereafter. Operation 406 is performed in responseto the another endurance tier having the insufficient storage for thedata in the section in the current endurance tier.

With reference next to FIG. 5, a flowchart of a process for configuringa storage system is depicted in accordance with an illustrativeembodiment. The process in FIG. 5 can be implemented in hardware,software, or both. When implemented in software, the process can takethe form of program code that is run by one or more processor unitslocated in one or more hardware devices in one or more computer systems.For example, the process can be implemented in storage manager 216 incomputer system 218 in FIG. 2. This process can be used to configure orreconfigure solid state storage devices 208 into endurance tiers 210 forstorage system 204.

The process begins by grouping solid state storage devices intoendurance tiers based on classes of storage for the solid state storagedevices (step 500). The classes are based on maximum write ratesspecified by a manufacturer. In this example, the solid state storagedevices in an endurance tier all have the same maximum write rates. Insome illustrative examples, the storage devices in the endurance tiercould have write rates that vary within a range.

The process selects a maximum recommended write rate class for eachendurance tier (step 502). These maximum recommended write rates areselected as being below the maximum write rate specified by themanufacturer.

The process selects a minimum recommended write rate for each endurancetier (step 504). The process terminates thereafter. In step 504, theminimum recommended write rate can be based on the maximum write ratesof lower endurance classes with a percentage threshold as a buffer. Thepercentage threshold provides some difference between the classes. Theselection of the buffer can be made to avoid data with fluctuating writerates that do not exceed the maximum recommended write rate in theendurance tier in which the data is located and to avoid excess movementof the same piece of data back and forth between the endurance tiers.

Turning now to FIG. 6, a flowchart of a process for provisioning astorage system is depicted in accordance with an illustrativeembodiment. The process in FIG. 6 can be implemented in hardware,software, or both. When implemented in software, the process can takethe form of program code that is run by one or more processor unitslocated in one or more hardware devices in one or more computer systems.For example, the process can be implemented in storage manager 216 incomputer system 218 in FIG. 2. This process can be used to provisionsolid state storage devices 208 in storage system 204 in FIG. 2.

The process begins by receiving a request to create a new logical unitnumber (LUN) for a volume in a storage system (step 600). In thisexample, the request can also indicate the performance is at the levelprovided by a solid state storage device instead of a device that uses aspinning disk.

The process receives an expected write level for the new logical unitnumber (step 602). In step 602, the write level can be the amount ofdata expected to be written to the logical unit number on a daily basis.

The process creates volume on an endurance tier that has a maximumrecommended write rate that is greater than the write level received(step 604). The process terminates thereafter.

The flowcharts and block diagrams in the different depicted embodimentsillustrate the architecture, functionality, and operation of somepossible implementations of apparatuses and methods in an illustrativeembodiment. In this regard, each block in the flowcharts or blockdiagrams may represent at least one of a module, a segment, a function,or a portion of an operation or step. For example, one or more of theblocks can be implemented as program code, hardware, or a combination ofthe program code and hardware. When implemented in hardware, thehardware may, for example, take the form of integrated circuits that aremanufactured or configured to perform one or more operations in theflowcharts or block diagrams. When implemented as a combination ofprogram code and hardware, the implementation may take the form offirmware. Each block in the flowcharts or the block diagrams can beimplemented using special purpose hardware systems that perform thedifferent operations or combinations of special purpose hardware andprogram code run by the special purpose hardware.

In some alternative implementations of an illustrative embodiment, thefunction or functions noted in the blocks may occur out of the ordernoted in the figures. For example, in some cases, two blocks shown insuccession can be performed substantially concurrently, or the blocksmay sometimes be performed in the reverse order, depending upon thefunctionality involved. Also, other blocks can be added in addition tothe illustrated blocks in a flowchart or block diagram.

Turning now to FIG. 7, a block diagram of a data processing system isdepicted in accordance with an illustrative embodiment. Data processingsystem 700 can be used to implement server computer 104, server computer106, client devices 110, in FIG. 1. Data processing system 700 can alsobe used to implement computer system 218 in FIG. 2. In this illustrativeexample, data processing system 700 includes communications framework702, which provides communications between processor unit 704, memory706, persistent storage 708, communications unit 710, input/output (I/O)unit 712, and display 714. In this example, communications framework 702takes the form of a bus system.

Processor unit 704 serves to execute instructions for software that canbe loaded into memory 706. Processor unit 704 includes one or moreprocessors. For example, processor unit 704 can be selected from atleast one of a multicore processor, a central processing unit (CPU), agraphics processing unit (GPU), a physics processing unit (PPU), adigital signal processor (DSP), a network processor, or some othersuitable type of processor. Further, processor unit 704 can may beimplemented using one or more heterogeneous processor systems in which amain processor is present with secondary processors on a single chip. Asanother illustrative example, processor unit 704 can be a symmetricmulti-processor system containing multiple processors of the same typeon a single chip.

Memory 706 and persistent storage 708 are examples of storage devices716. A storage device is any piece of hardware that is capable ofstoring information, such as, for example, without limitation, at leastone of data, program code in functional form, or other suitableinformation either on a temporary basis, a permanent basis, or both on atemporary basis and a permanent basis. Storage devices 716 may also bereferred to as computer-readable storage devices in these illustrativeexamples. Memory 706, in these examples, can be, for example, arandom-access memory or any other suitable volatile or non-volatilestorage device. Persistent storage 708 may take various forms, dependingon the particular implementation.

For example, persistent storage 708 may contain one or more componentsor devices. For example, persistent storage 708 can be a hard drive, asolid-state drive (SSD), a flash memory, a rewritable optical disk, arewritable magnetic tape, or some combination of the above. The mediaused by persistent storage 708 also can be removable. For example, aremovable hard drive can be used for persistent storage 708.

Communications unit 710, in these illustrative examples, provides forcommunications with other data processing systems or devices. In theseillustrative examples, communications unit 710 is a network interfacecard.

Input/output unit 712 allows for input and output of data with otherdevices that can be connected to data processing system 700. Forexample, input/output unit 712 may provide a connection for user inputthrough at least one of a keyboard, a mouse, or some other suitableinput device. Further, input/output unit 712 may send output to aprinter. Display 714 provides a mechanism to display information to auser.

Instructions for at least one of the operating system, applications, orprograms can be located in storage devices 716, which are incommunication with processor unit 704 through communications framework702. The processes of the different embodiments can be performed byprocessor unit 704 using computer-implemented instructions, which may belocated in a memory, such as memory 706.

These instructions are referred to as program code, computer usableprogram code, or computer-readable program code that can be read andexecuted by a processor in processor unit 704. The program code in thedifferent embodiments can be embodied on different physical orcomputer-readable storage media, such as memory 706 or persistentstorage 708.

Program code 718 is located in a functional form on computer-readablemedia 720 that is selectively removable and can be loaded onto ortransferred to data processing system 700 for execution by processorunit 704. Program code 718 and computer-readable media 720 form computerprogram product 722 in these illustrative examples. In the illustrativeexample, computer-readable media 720 is computer-readable storage media724.

In these illustrative examples, computer-readable storage media 724 is aphysical or tangible storage device used to store program code 718rather than a medium that propagates or transmits program code 718.

Alternatively, program code 718 can be transferred to data processingsystem 700 using a computer-readable signal media. The computer-readablesignal media can be, for example, a propagated data signal containingprogram code 718. For example, the computer-readable signal media can beat least one of an electromagnetic signal, an optical signal, or anyother suitable type of signal. These signals can be transmitted overconnections, such as wireless connections, optical fiber cable, coaxialcable, a wire, or any other suitable type of connection.

Further, as used herein, “computer-readable media 720” can be singularor plural. For example, program code 718 can be located incomputer-readable media 720 in the form of a single storage device orsystem. In another example, program code 718 can be located incomputer-readable media 720 that is distributed in multiple dataprocessing systems. In other words, some instructions in program code718 can be located in one data processing system while otherinstructions in in program code 718 can be located in one dataprocessing system. For example, a portion of program code 718 can belocated in computer-readable media 720 in a server computer whileanother portion of program code 718 can be located in computer-readablemedia 720 located in a set of client computers.

The different components illustrated for data processing system 700 arenot meant to provide architectural limitations to the manner in whichdifferent embodiments can be implemented. In some illustrative examples,one or more of the components may be incorporated in or otherwise form aportion of, another component. For example, memory 706, or portionsthereof, may be incorporated in processor unit 704 in some illustrativeexamples. The different illustrative embodiments can be implemented in adata processing system including components in addition to or in placeof those illustrated for data processing system 700. Other componentsshown in FIG. 7 can be varied from the illustrative examples shown. Thedifferent embodiments can be implemented using any hardware device orsystem capable of running program code 718.

Thus, illustrative embodiments of the present invention provide acomputer-implemented method, computer system, and computer programproduct for managing a storage system. Writes to sections in solid statestorage devices in endurance tiers in the storage system are monitoredby a computer system over a period of time. Responsive to a write ratefor the writes to a section in the sections in a current endurance tierin the endurance tiers exceeding a maximum recommended write rate forthe current endurance tier during the period of time, data is moved fromthe section in the current endurance tier to a higher endurance tier inthe endurance tiers having a higher maximum recommended write rate thanthe maximum recommended write rate for the current endurance tier.

In one illustrative example, a storage manager in a computer system isdirected to a practical application of processes integrated into thestorage manager to monitor writes to solid state storage devicesorganized in endurance tiers having a hierarchy in which the hierarchyis based on maximum recommended write rates for the solid state storagedevices. When writes for a section exceed a maximum recommended writerate for a particular endurance tier, the data in that section can bemoved to another endurance tier in the hierarchy having a higher maximumrecommended write rate that is sufficient for the rate detected. Thedata with higher write rates can be moved to higher endurance tiers and,in a similar fashion, data with writes can be moved to lower endurancetiers.

As a result, exceeding manufacturer write rates can be avoided using astorage manager as shown in the illustrative example. By not exceedingmanufacturer write rates, the life of the solid state storage devices ina storage system can be extended and the voiding of warranties for thesolid state storage devices can be avoided. Further, this also reducesthe amount of effort needed to organize solid state storage devicesbased on particular uses for expected writes to the storage system.Instead, the storage manager can manage the deduplication data withinthe storage system based on the writes and maximum recommended writerates the solid state storage devices.

Further, in the illustrative examples, undesired and unexpected failuresin solid state storage devices can be reduced or avoided using a storagemanager as shown in the illustrative example to manage writes of data tothe solid state storage devices. Further, the reliability of thecomputer system with respect to storing data can be improved as comparedto current computer systems that do not employ storage manager asdescribed in the illustrative examples. This type of management of datausing endurance tiers with maximum recommended write rates can take intovariations and uses for individual volumes and can also provideincreased granular management of where particular solid state devicesare placed into different endurance tiers.

The description of the different illustrative embodiments has beenpresented for purposes of illustration and description and is notintended to be exhaustive or limited to the embodiments in the formdisclosed. The different illustrative examples describe components thatperform actions or operations. In an illustrative embodiment, acomponent can be configured to perform the action or operationdescribed. For example, the component can have a configuration or designfor a structure that provides the component an ability to perform theaction or operation that is described in the illustrative examples asbeing performed by the component. Further, To the extent that terms“includes”, “including”, “has”, “contains”, and variants thereof areused herein, such terms are intended to be inclusive in a manner similarto the term “comprises” as an open transition word without precludingany additional or other elements.

The descriptions of the various embodiments of the present inventionhave been presented for purposes of illustration, but are not intendedto be exhaustive or limited to the embodiments disclosed. Not allembodiments will include all of the features described in theillustrative examples. Further, different illustrative embodiments mayprovide different features as compared to other illustrativeembodiments. Many modifications and variations will be apparent to thoseof ordinary skill in the art without departing from the scope and spiritof the described embodiment. The terminology used herein was chosen tobest explain the principles of the embodiment, the practical applicationor technical improvement over technologies found in the marketplace, orto enable others of ordinary skill in the art to understand theembodiments disclosed here.

1. A method for managing a storage system, the method comprising:monitoring, by a computer system, writes to sections in solid statestorage devices in endurance tiers in the storage system over a periodof time; and responsive to a write rate for the writes to a section inthe sections in an current endurance tier in the endurance tiersexceeding a maximum recommended write rate for the current endurancetier during the period of time, moving data from the section in thecurrent endurance tier to a higher endurance tier in the endurance tiershaving a higher maximum recommended write rate than the maximumrecommended write rate for the current endurance tier.
 2. The method ofclaim 1, further comprising: responsive to the write rate for the writesto the section in the current endurance tier falling below a minimumrecommended write rate for the current endurance tier during the periodof time, moving the data from the section in the current endurance tierto a lower endurance tier in the endurance tiers with a lower minimumrecommended write rate than the minimum recommended write rate for thecurrent endurance tier.
 3. The method of claim 1, further comprising:determining whether another endurance tier has sufficient storage fordata in the section in the current endurance tier in response to anotherendurance tier being selected to perform a movement of the data; andgenerating an alert indicating that insufficient storage is present forthe movement of the data in response to the another endurance tierhaving the insufficient storage for the data in the section in thecurrent endurance tier.
 4. The method of claim 1, wherein the writesmeasured as one of a running daily average, an average during the periodof time, or an aggregate total for the period of time.
 5. The method ofclaim 1, wherein the maximum recommended write rates are lower than themaximum write rate specified by a manufacturer of the solid statestorage devices in the current endurance tier.
 6. The method of claim 2,wherein the minimum recommended write rate for the current endurancetier is based on the maximum recommended write rate of the lowerendurance tier.
 7. The method of claim 1, wherein the section isselected from one of a segment, an extent, and a data block, and furthercomprising: receiving a request to create a new logical unit number fora volume in the storage system; receiving an expected write level forthe new logical unit number; and creating the volume on an endurancetier of the endurance tiers that has a maximum recommended write ratethat is greater than the received expected write level for the newlogical unit number.
 8. The method of claim 1, wherein the solid statestorage devices in the endurance tiers are selected from at least one ofa solid state disk or a flash drive, and further comprising: groupingthe solid state storage devices in the endurance tiers based on maximumrecommended write rates for the solid state storage devices specified byat least one manufacturer of the solid state storage devices; andselecting a minimum recommended write rate for the each endurance tierthat is below the maximum recommended write rate for the each endurancetier.
 9. A storage management system comprising: a computer system thatmonitors writes to sections in solid state storage devices in endurancetiers of in a storage system over a period of time and responsive to awrite rate for the writes to a section in the sections in an currentendurance tier in the endurance tiers exceeding a maximum recommendedwrite rate for the current endurance tier during the period of time,moves data from the section in the current endurance tier to a higherendurance tier in the endurance tiers having a higher maximumrecommended write rate than the maximum recommended write rate for thecurrent endurance tier.
 10. The storage management system of claim 9,wherein the computer system, responsive to the write rate for the writesto the section in the current endurance tier falling below a minimumrecommended write rate for the current endurance tier during the periodof time, moves the data from the section in the current endurance tierto a lower endurance tier in the endurance tiers with a lower minimumrecommended write rate than the minimum recommended write rate for thecurrent endurance tier.
 11. The storage management system of claim 9,wherein the computer system determines whether another endurance tierhas sufficient storage for the data in the section in the currentendurance tier in response to another endurance tier being selected toperform a movement of the data; and generates an alert indicating thatinsufficient storage is present for the movement of the data in responseto the another endurance tier having the insufficient storage for thedata in section in the current endurance tier.
 12. The storagemanagement system of claim 9, wherein the writes are measured as one ofa running daily average, an average during the period of time, or anaggregate total for the period of time.
 13. The storage managementsystem of claim 9, wherein the maximum recommended write rates are lowerthan the maximum write rate specified by a manufacturer of the solidstate storage devices in current endurance tier.
 14. The storagemanagement system of claim 10, wherein the minimum recommended writerate for the current endurance tier is based on the maximum recommendedwrite rate of the lower endurance tier.
 15. The storage managementsystem of claim 9, wherein the section is selected from one of asegment, an extent, and a data block, and further comprising: receivinga request to create a new logical unit number for a volume in thestorage system; receiving an expected write level for the new logicalunit number; and creating the volume on an endurance tier of theendurance tiers that has a maximum recommended write rate that isgreater than the received expected write level for the new logical unitnumber.
 16. The storage management system of claim 9, wherein the solidstate storage devices in the endurance tiers are selected from at leastone of a solid state disk or a flash drive, and further comprising:grouping the solid state storage devices in the endurance tiers based onmaximum recommended write rates for the solid state storage devicesspecified by at least one manufacturer of the solid state storagedevices; and selecting a minimum recommended write rate for the eachendurance tier that is below the maximum recommended write rate for theeach endurance tier.
 17. A computer program product for managing astorage system, the computer program product comprising: acomputer-readable storage media; first program code, stored on thecomputer-readable storage media, executable by a computer system tocause the computer system to monitor writes to sections in solid statestorage devices in endurance tiers of in the storage system over aperiod of time; and second program code, stored on the computer-readablestorage media, executable by a computer system to cause the computersystem to move data from a section in the sections in a currentendurance tier to a higher endurance tier in the endurance tiers havinga higher maximum recommended write rate than a maximum recommended writerate for the current endurance tier in response to the write rate forthe writes to the section exceeding the maximum recommended write ratefor the current endurance tier during the period of time.
 18. Thecomputer program product of claim 17, further comprising: third programcode, stored on the computer-readable storage media, executable by acomputer system to cause the computer system to move the data from thesection in the current endurance tier to a lower endurance tier in theendurance tiers with a lower minimum recommended write rate than aminimum recommended write rate for the current endurance tier inresponse to the write rate for the writes to the section in the currentendurance tier falling below the minimum recommended write rate for thecurrent endurance tier during the period of time.
 19. The computerprogram product of claim 17, further comprising: third program code,stored on the computer-readable storage media, executable by a computersystem to cause the computer system to determine whether anotherendurance tier has sufficient storage for the data in the section in thecurrent endurance tier in response to another endurance tier beingselected to perform a movement of the data; and fourth program code,stored on the computer-readable storage media, executable by a computersystem to cause the computer system to generate an alert indicating thatinsufficient storage is present for the movement of the data in responseto the another endurance tier having the insufficient storage for thedata in section in the current endurance tier.
 20. The computer programproduct of claim 17, wherein the writes are measured as one of a runningdaily average, an average during the period of time, or an aggregatetotal for the period of time.